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141.
142.
Gregory P. Moore MD JD 《Academic emergency medicine》2001,8(4):389-392
The use of the newly dead to teach procedures is widely practiced in training institutions. This model allows a realistic opportunity both to become more familiar with lifesaving maneuvers before they are actually necessary and to maintain proficiency. Whether to notify the next of kin first has been an issue of ethical debate. Some argue a "don't ask, don't tell" policy is justified, while others mandate open consent by family members prior to the practice. Several medical studies have found that patients and families are likely to consent to the procedures but prefer to be asked permission first. Multiple legal cases have addressed the issue of usage of cadavers postmortem without expressed permission. Earlier cases emphasized the concept of "pseudo-property" rights and declared that the next of kin do not have constitutional ownership of the deceased person's body. More recent legal cases are declaring that families do, in fact, possess these rights. In this day and age of increasing recognition of personal autonomy, it is probably prudent to approach the next of kin for permission before performing procedures on the newly deceased. 相似文献
143.
The authors report 2.5 years' experience with the use of cytomegalovirus (CMV)-seronegative blood components for the prevention of primary CMV infection after allogeneic marrow transplantation from seronegative marrow donors to 104 CMV-seronegative patients. Patients and blood donors were screened for CMV-seronegativity by a combination of passive latex agglutination, complement fixation, and indirect hemagglutination CMV antibody screening methods. Changes in blood banking procedures necessary to provide CMV-seronegative components are detailed. Providing CMV-seronegative components was a considerable undertaking; a mean, per patient, of 19 units of red cells and 105 units of platelets was required. Twenty percent of the platelet support was provided by family members and 80 percent by volunteer donors. CMV-infection was eliminated in all but one patient not considered infected at the time of transplantation. The capability to provide CMV-seronegative components depends on an adequate supply of seronegative donors, a sensitive and practical screening method for CMV antibody, a major commitment by the blood bank, and close communication between the blood bank and the patients' physicians. 相似文献
144.
145.
STEWART AJ; ALLEN JD; ADGEY AAJ 《QJM : monthly journal of the Association of Physicians》1992,85(1):761-769
SUMMARY In 56 patients, frequency analysis of the electrocardiogramof ventricular fibrillation exhibited power spectra with a distinctdominant frequency. The greatest success for resuscitation fromventricular fibrillation is recorded when ventricular fibrillationdevelops after the patient comes under coronary care. Of the41 patients in whom the onset and first 8 s of ventricular fibrillationwere artefact-free the mean dominant frequency of primary ventricularfibrillation (no cardiogenic shock or cardiac failure) in 21patients was 6.2±0.2 Hz, significantly higher than themean dominant frequency of the first 8 s of secondary ventricularfibrillation (cardiogenic shock or heart failure) (4.0±0.2Hz, 20 patients, p =0.0001). In these patients the peak-to-troughamplitude (ECG) of the first 8 s of ventricular fibrillationwas similar in both primary and secondary ventricular fibrillationas was the mean duration of ventricular fibrillation prior tothe first DC shock. There was a significantly lower successrate for resuscitation from secondary ventricular fibrillation(6 of 20 patients) compared with resuscitation from primaryventricular fibrillation (18 of 21 patients, x2 17.8, p=0.001).Of the remaining 15 patients who were collapsed between 3 and20 min before the arrival of the mobile coronary care unit,the dominant frequency of the first 8 s of ventricular fibrillationfell with increased duration of collapse (from 5.5 Hz at 3 minto a mean of 2.1 Hz at 20 min). Four of these 15 patients whosurvived the initial arrest had a mean dominant frequency of5.2±0.3 Hz, which was significantly higher than the meandominant frequency (3.1±0.3 Hz, p<0.01) of the 11patients who were not resuscitated. This study shows that low frequency ventricular fibrillationis indicative of a poor chance of successful resuscitation.Alteration of the frequency may increase resuscitation success. 相似文献
146.
A Arduini ; S Holme ; JD Sweeney ; S Dottori ; AF Sciarroni ; M Calvani 《Transfusion》1997,37(2):166-174
BACKGROUND: The role of L-carnitine (LC) as the requisite carrier of long-chain fatty acids into mitochondria is well established. Human red cells (RBCs), which lack mitochondria, possess a substantial amount of LC and its esters. In addition, carnitine palmitoyl transferase, an enzyme that catalyzes the reversible transfer of the acyl moiety from acyl-coenzyme A to LC is found in RBCs. It has recently been shown that LC and carnitine palmitoyl transferase play a major role in modulating the pathway for the turnover of membrane phospholipid fatty acids in intact human RBCs, and that LC improved the membrane stability of RBCs subjected to high shear stress. RBC membrane lesions occur during storage at 4 degrees C; this study investigated whether the addition of LC (5 mM) to a standard RBC preservative solution (AS-3) affected cellular integrity with 42 days' storage. STUDY DESIGN AND METHODS: A paired (n = 10) crossover design was used for RBCs stored in AS-3 with and without LC. Both in vitro RBC properties reflective of metabolic and membrane integrity and in vivo measures of cell viability (24-hour percentage of recovery and circulating lifespan) were measured at the end of the storage. In addition, the turnover of membrane phospholipid and long-chain acylcarnitine fatty acids and the carnitine content of control and LC-stored RBCs were measured. RESULTS: It was shown that LC was irreversibly taken up by RBCs during storage, with a fourfold increase at 42 days. Furthermore, as found by the use of radiolabeled palmitate, the stored RBCs were capable of generating long-chain acylcarnitine. The uptake of LC during storage was associated with less hemolysis and higher RBC ATP levels and by a significantly greater in vivo viability for LC-stored RBCs than for control-stored RBCs: a mean 24-hour percentage of recovery of 83.9 +/? 5.0 vs. 80.1 +/? 6.0 percent and a mean lifespan of 96 +/? 11 vs. 86 +/? 14 days, respectively (p < 0.05). CONCLUSION: A beneficial effect of the addition of LC to RBCs stored at 4 degrees C was evident. This effect may be related to both biophysical and metabolic actions on the cell membrane. 相似文献
147.
148.
The Viral Activation Transfusion Study (VATS): rationale, objectives, and design overview 总被引:1,自引:0,他引:1
149.
150.
Robert M. McNamara MD Theodore W. Whitley PhD Arthur B. Sanders MD Louise B. Andrew MD JD For the SAEM In-service Survey Task Force 《Academic emergency medicine》1995,2(4):293-301
OBJECTIVE: To determine the extent and effects of abuse and harassment, including sexual harassment and racial or ethnic discrimination, experienced by residents in emergency medicine (EM). METHOD: The study instrument was an anonymous, self-report survey administered to a national sample of EM residents. The survey was timed to coordinate with the American Board of Emergency Medicine's annual In-Service Examination in February 1993. The residents reported whether they had experienced nine types of abuse or harassment during their residency training, the sources of these incidents, the effects on the residents, and whether they chose to file a formal complaint regarding these events. RESULTS: Surveys were returned by 1,774 (80%) of the 2,229 residents who sat for the examination--74.4% men and 24.6% women. Overall, 98% reported at least one occurrence of abuse or harassment, with patients being the most frequent source. More than half of the more senior residents reported having been physically hit or pushed. Other health care professionals were a frequent source of verbal abuse and sexual harassment. Women were significantly more likely than men to report unwanted sexual advances (63% vs 32%, p < 0.001), discomfort from sexual humor (66% vs 27%, p < 0.001), and unfair treatment because of gender (71% vs 15%, p < 0.001). Non-Caucasians reported a higher rate of racial or ethnic discrimination than did Caucasians (51% vs 23%, p < 0.001). As a result of these episodes, 19% of the respondents had questioned their decision to become a physician, 20% had questioned entering the specialty of EM, 11% had experienced emotional effects lasting over one month, and 11% had experienced disruption of their family lives. Only 56 (3.2%) had filed formal complaints. CONCLUSIONS: Residents frequently encounter abuse or harassment, particularly from patients. They also report adverse consequences from these episodes. 相似文献